SPECIAL TOPIC : Actuation & Automation
Continuous Motion
The ability for continuous motion or valve throttling can be achieved with SMA bundled wire actuators without limitations typical of motorized systems . Motorized systems ( i . e ., electricmotor actuators or air compressors ) require periods of rest between operations to prevent damage caused by overheating or wear to components . A common strategy that mitigates continuous operation in motors is to introduce deadband , a period of intentional non-responsiveness to small motion commands . Employing this strategy , however , results in lag or system latency , which can manifest into positional error and instability in process control applications .
SMA bundled wire actuators can run continuously with a 100 % duty cycle and can immediately respond to commands without deadband limitations . The motion developed by the actuator is smooth and responsive to changes in position command . The length of the SMA wires can be controlled to a fine degree , enabling SMA bundled wire actuators to achieve positional precision of under 50 microns ( 0.002 inch ).
Scalable and Flexible
SMA bundled wire actuators can be adapted to meet a wide range of applications and use cases . The actuator ’ s force , travel , and idle position can be engineered to suit a variety of valve sizes , types , and applications . Additionally , SMA bundled wire actuators
Figure 3 : Performance of a field-deployed SMA bundled wire actuator in a continuous modulating / throttling backpressure valve application at a natural gas production facility , the absolute average error was less than 50 μm [. 002 inch ].
can be configured to work with either AC ( alternating current ) or DC ( direct current ) power at industry-typical voltage levels ( eg . 24 VDC or 120 VAC ), allowing them to be integrated into facility infrastructure or remote locations that have limited power options .
Performance Testing and Field Trials
Faced with the challenge of transitioning away from methane venting pneumatic equipment , an SMA bundled wire actuator was developed by Kinitics Automation for the Canadian natural gas industry .
The development of the SMA bundled wire actuator included third party lab testing and field trials with partners including the University of Calgary and major natural gas producers in Canada . Testing and field trials of the product were crucial for validating its performance in extreme environments typical of industrial applications within the sector .
Third party testing of the actuator was conducted at the NGIF Emissions Testing Centre ( ETC ) Lab at the University of Calgary . Testing at the ETC was aimed to assess the positioning performance of the actuator under different environmental temperature conditions and its capability to generate sufficient force for sustaining a pressure differential across a closed valve . Testing was conducted in environments between -43 ° C and + 46 ° C to validate the actuator ’ s performance at temperature extremes . The actuators ’ ability to generate closing force was verified under gas pressure . Testing of positional performance found the deadband to be smaller than 0.25 % ( 50 µ m ) and positional accuracy was found to be within 0.1 % ( 19 µ m ) across all temperature conditions .
The SMA bundled wire actuator was certified to operate in both ordinary and hazardous locations ( Canada & US Class I , Zone 1 AEx db IIA T6 Gb ) and has been deployed at various operational sites of major natural gas producers for field trials including a Tourmaline Oil Corp . natural gas production well site near Edson , Alberta , Figure 1 . Three actuators were deployed on a test separator at this site with one actuator used for backpressure control , a continuous throttling application , and two actuators for snap action level control . The actuators were installed in late 2022 and data shows the actuators to have high uptime and high positional performance . Data acquired from the backpressure control valve showed an average error of less than 0.5 % during a 12-day period where the valve was in a constant throttling mode , Figure 3 .
The field site employed a natural gas generator that produced electric power for the site ’ s facility and equipment . A power system fault occurred in February 2023 that resulted in a power outage . During this time , a battery-powered data acquisition system was able to capture the behavior of the SMA bundled wire actuators during this power loss event which showed that the actuators were able to move into and hold a closed position when unpowered .
Conclusion
The introduction of an SMA bundled wire actuator presents the industrial valve sector with a new method of valve control . The use of SMA technology allows for reduced maintenance requirements , improved accuracy and reliability , and electric control with spring closure . Rigorous lab testing and realworld field trials validate the technology for durability in industrial environments . The introduction of SMA bundled wire actuators indicates a promising future for SMA technology , underlining its potential to redefine principles for industrial valve actuators and help pave the way for a more sustainable energy sector .
ABOUT THE AUTHOR
Adam Nguyen is an Automation Solutions Specialist at Kinitics Automation . He is dedicated to pushing the boundaries of technology in robotics , computer vision , and industrial automation . His commitment to innovation fuels his work , with a goal for a more advanced and sustainable world through cutting-edge solutions .
www . valve-world-americas . net • September 2023 | Valve World Americas 5